Papers by Author: Xing Guo Li

Abstract: Nearly monodispersed SiO2 nanospheres, with different size and size standard deviation smaller than 5%, have been prepared by using batch/semibatch process. The SiO2 colloids were used as building blocks to self-assemble into the colloidal crystals, which photonic band gaps are close to the theoretical values, and can be modified by changing the size SiO2 nanospheres. With the increase of the size of SiO2 spheres, the photonic band gap red shift.

Abstract: Mg, Ni and Cu nanoparticles were prepared by hydrogen plasma-metal reaction method. Nanostructured Mg2Ni and Mg2Ni0.75Cu0.25 compound were successfully obtained using the metal nanoparticles. The synthesis mechanism, the structure and lattice parameter difference, and the hydrogen absorption behaviors of the two compounds were discussed.

Abstract: Fe61Co39 nanoparticles were prepared by hydrogen plasma metal reaction. The as-synthesized nanoparticles were characterized by x-ray differaction (XRD), transimition electron microscope (TEM) and superconducting quantum interference device (SQUID). The nanoparticles are spherical in shape, have bcc structure with the mean particle diameter of 41 nm, and are basically ferromagnetic with a slight amount of superparamagnetic part. The saturation magnetization and coercivity of the nanoparticles at 4.2 K are 190.15 emu/g and 1280 Oe, respectively. The blocking temperature is 250 K in 100 Oe and decreases with increasing the magnetic field.